TUMOURS OF THE SALIVARY GLANDS. 335 



and the posterior auricular artery ; the facial nerve and its three 

 auricular branches, and the superficial temporal nerve ; and the 

 guttural pouch, which lies beneath the upper extremity of the gland. 

 Finally, the wound is douched with a weak antiseptic, powdered 

 with iodoform and tannin, covered with a thin layer of absorbent 

 cotton, closed with catgut sutures, and protected with an antiseptic 

 compress and a roller bandage. 



(6.) TUMOURS OF THE SALIVARY GLANDS. 



The nature of new growths occurring in the sa^vary glands of 

 animals has not hitherto been fully or sufficiently investigated. In 

 man, connective tissue tumours, such as sarcomata, fibromata, and 

 enchondromata, are most frequent. The tumours so common in grey 

 horses are usually melano-sarcomata, and in cattle actino mycotica. 

 As little is known of the causes of these new growths as of other 

 tumours. Cohnhein refers the development of enchondroma to 

 cartilaginous fragments of the branchial arch. Actinomycosis depends 

 on infection. 



Their sharply denned appearance, slow development, and the 

 absence of inflammatory symptoms, render the diagnosis of tumours 

 comparatively easy. Their precise nature, however, can usually 

 only be determined by microscopical examination. Actinomycosis 

 will be referred to later. 



Treatment must clearly be of an operative character. Simple, 

 sharply defined tumours can easily be removed with knife or scissors. 

 By careful suturing and appropriate treatment of the wound, it is 

 easy to avoid producing salivary fistulse. Large and extended 

 tumours may necessitate removal of the entire gland. Total extir- 

 pation of the parotid is attended with danger, and therefore should 

 only be resolved on in case of pressing necessity, as when dyspnoea 

 is produced by the tumour, or when exceptionally valuable animals, 

 which must not be slaughtered, have to be dealt with. Leblanc is 

 said to have first performed this operation, and to have employed 

 it both for removal of tumours and for the cure of salivary fistula?. 

 The operating place should be well lighted, and aseptic precautions 

 are, of course, necessary. Operation may be carried out by the 

 method described under "salivary fistulse," or as follows : — ■ 



The skin is divided from the upper to the lower end of the parotid, 

 and where adherent to the tumour, is removed. In large animals a 

 second incision is usually carried in a backward direction perpendicular 



